JP2005178745A - Storage system for antenna and storage method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and efficiently mount an assembly to a tire. <P>SOLUTION: In an antenna system and a method for a tire monitoring system, a pipe-like antenna housing 36 constituted by a material having suitable flexibility is used. The antenna 32 is stored in the housing 36 in a straight shape or in another preferable shape such as a sine curve. The pipe-like housing 36 may be straight and may be provided with a corrugated wall in order to be provided with further flexibility. Electronic part packages 34 are provided on opposite surfaces of the antenna housing 36 respectively and may be provided with ends having a dimension and a shape fitted to the opposed ends of the antenna tube 36 respectively. When the end of the housing 38 of the electronic part is fitted to the end of the tube 36, the antenna tube 36 is firmly fixed to the electronic part package 34. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates generally to an apparatus including an antenna and a transponder for a tire pressure monitoring system, and more particularly to an antenna storage system and method for a tire pressure monitoring system.

  An annular device including an antenna that electronically transmits tire and wheel identification information and other data at a radio frequency is generally used. The apparatus includes a radio frequency transponder with an integrated circuit chip having sufficient data capacity to hold at least tire or wheel identification information. Other data, such as tire pressure and tire and wheel temperature at the transponder location, are transmitted by the transponder along with identification information.

  It is known in the art to provide an annular antenna that transmits data at radio frequencies from a transponder contained within the structure of a tire or tire-wheel assembly. The antenna is a wire or wire strand formed in a loop shape that can be housed in a cover extruded from a suitable material such as plastic. The plastic sheath, in combination with the antenna, forms a monolith that can be attached to the green tire in the assembly process prior to tire assembly or to the finished tire in the post-curing process. The antenna and transponder may be incorporated into the tire in a “pre-curing” tire assembly process, but in practice this is very difficult to do. Both radial ply tires and bias ply tires are substantially diametrically expanded in the manufacturing process. Bias-ply tires are diametrically expanded when inserted into a curing press that typically has a bladder that forces a green tire into a toroidal mold. Radial ply tires are diametrically expanded during the tire assembly or forming process and further diametrically expanded during the curing process. Any annular antenna built into the tire and the circuit components connected to it are structurally sound and mechanically connected between the antenna and transponder package when the tire is diametrically expanded during the manufacturing process. Must be able to maintain the department. Once assembled into a tire, if an irreparable defect is found in the antenna, transponder, or antenna-transponder connection, the usefulness of the tire is lost and the tire may need to be discarded. Thus, attaching an annular antenna transponder assembly to a tire during tire manufacture was sound if it was otherwise attached if the assembly parts were later damaged or broken There is a risk that it will have to break the tire it is attached to.

  The risk of damage to the annular antenna transponder system is not only not only when it is incorporated into the tire during manufacture, but it is not uncommon to arise from the movement of the tire attached to the vehicle. The loop antenna and the electronic component connected to the loop antenna are substantially subjected to compressive strain, and a large strain amplitude is applied to the sidewall. Such a location is a typical tire region that is subject to large loads and deformations. Therefore, the antenna, the transponder, and their connection portions are susceptible to breakage, mechanical and electrical damage when in such a place.

  In order to protect the electronic components from being exposed to the harsh environment of the tire curing cycle, it has been proposed to attach the annular antenna device after curing. The antenna assembly is formed by extracting rubber onto the antenna in a specific shape, typically annulus, and then the antenna assembly is cured. The antenna in the cured composite is then passed through the electronic component package. Finally, the rubber composite and electronic component package are re-cured with the rubber. The annular antenna assembly is then bonded to the inside of the tire sidewall as a finished product.

  Such antenna assemblies and assembly methods are good, but due to several drawbacks, they cannot be a complete solution to the needs of the industry. First, it is not possible to provide the antenna loop with a sufficient degree of freedom to move the antenna wire into the elastic sheath while protecting the antenna wire. If the extension of the antenna is restricted in this way, the antenna may eventually be broken. Next, the step of attaching the electronic component package to the antenna wire and further curing the electronic component in the second step complicates the assembly process of the antenna device and increases the amount of labor. As a result, the assembly time increases and the cost of the finished tire is greatly increased.

  In view of the above, there is a continuing need for an antenna device and method of attachment that allows an assembly to be easily and efficiently attached to a tire. The method preferably attaches the antenna assembly to the electronic component package in a post-curing step to protect the electronic component from the harsh environment during the tire curing cycle. The antenna device must have sufficient structural integrity to withstand the stress associated with the use of a tire attached to the vehicle and to protect the structural integrity of the antenna in such an environment. Furthermore, it is desirable that the antenna device ideally maintain the antenna in an optimal, intended configuration and shape throughout the life of the tire. The performance of a tire pressure monitoring system depends on effective communication between the tire electronics and the reader away from it, so maintaining the antenna in an optimal shape is very This is desirable. Furthermore, it is desirable that the antenna assembly and assembly method provide a means for connecting the antenna cable and the electronic component package in a post-cure process that is cost-effective and reliable.

  The present invention overcomes the shortcomings of known antenna systems and methods for tire monitoring systems by using a tubular antenna housing constructed of a material with suitable flexibility. The antenna is housed in the housing either straight or preferably in a sinusoidal, spiral or zigzag shape. Tubular housings have corrugated walls to provide straight or more flexibility. The tubular housing thus protects the antenna from corrosive gases and humidity in the tire space while allowing the antenna to bend and stretch unconstrained. In one embodiment of the present invention, the electronic component package may include an end portion that is provided on the opposite surface of the antenna housing and has a size and a shape that are respectively fitted to the opposite end portions of the antenna tube. . The end of the electronic component housing, when mated with the end of the tube, secures the antenna tube to the electronic component package. Subsequently, the antenna system may be glued to the tire space or otherwise attached to the tire space in a conventional manner. Such an assembling method includes a step of accommodating an extendable antenna cable in a tubular antenna housing having a hole extending in the axial direction in the center portion and both ends of the hole being opened, and each end portion of the tube. An electronic component is accommodated in a package having an end formed in a shape and size that can be fitted, a step of connecting both ends of the antenna cable to the electronic component accommodated in the package, and an antenna housing. A step of fitting both ends of the package to both ends of the antenna tube for attachment to the electronic component package.

  The advantages of the present invention, as will be apparent to those skilled in the art, are realized by the preferred and other embodiments described in detail below and illustrated by the accompanying drawings.

  Tire pressure monitoring systems typically consist of a transponder with one or more sensors. The transponder and electronic components connected to the transponder are housed in a package. The transponder needs to have an antenna in order to transmit and receive radio frequency signals. The antenna preferably has an annular shape in the present invention, but may take other shapes as required. The antenna may be incorporated in the tire during the manufacturing process, or may be attached to the tire in a post-manufacturing process. As used herein, an “annular antenna” may be circular, rectangular, symmetric, or asymmetric without departing from the principles of the present invention. However, the shape of the antenna is preferably circular, and is approximately the same size as the sidewall region to which the antenna is attached. Other locations for the assembly are possible, such as the top sidewall or the top region of the tire. The antenna can be composed of one wire or a plurality of stranded wires. Various commercially available transponders, sensors and other electronic components used in conjunction with annular antennas formed from conventional conductive materials can be used appropriately in harmony with the principles of the present invention.

  As a material for the antenna wire, steel, aluminum, copper, copper alloy, or other conductive wires can be used. As disclosed herein, the wire diameter is generally not considered critical for operation as a transponder antenna. In order to increase the durability, a multi-strand wire structure of a thin wire is desirable. Other options available include ribbon cables, ribbon conductors on woven stranded wires, flexible circuits, conductive films, conductive rubber, and the like.

  Referring to FIG. 1, a preferred embodiment of the present invention is shown deployed to the inside of a tire. The tire 12 is formed of a conventional material such as rubber or a rubber compound by a conventional method, and may have either a radial ply configuration or a bias ply configuration. A typical tire 12 includes a tread 14, a shoulder 16, an annular sidewall 18, and a terminal bead 20. An inner liner 22 is formed and defines a tire space 24. The tire 12 is adapted to be attached to an annular rim 26 having an outer rim flange 28 and an outer rim flange surface 30. The annular rim 26 has a conventional shape and is made of a metal having an appropriate strength such as steel.

  In a preferred embodiment, the annular antenna 32 has a sinusoidal shape. The antenna 32 may also be formed in another pattern, and may be one or more straight wires as needed, and may be a filament wire, cord, or stranded wire. Steel, aluminum, copper, or other conductive wires can be used as the wire material. As described above, it is generally considered that the wire diameter is not important for operation as an antenna, but a multi-strand wire structure of a thin wire is desirable. The antenna 32 has flexibility due to its curved or zigzag shape, and the risk of breakage during the manufacture and use of the tire described below is minimized.

  With continued reference to FIG. 1, a transponder module 34 of the general shape described above is provided. The transponder module 34 may include means for detecting parameters such as pressure and temperature. The storage tube 36 included as part of the device 10 is not essential, but is preferably formed in an annular shape as shown. As will be described below, the storage tube 36 is made of an elastic material having electrical insulation. Thus, in the as-manufactured state, the device 10 is a single, generally circular assembly having an antenna 32, a transponder module 34, and a containment tube 36 that is easy to transport and handle for attachment to the tire 12. is there. The diameter of the device assembly 10 is a function of the size of the tire 12 and the size of the desired appendages on the tire.

  Still referring to FIG. 1, the apparatus 10 is attached to the liner 22 of the tire 12, preferably in an assembly process after manufacture. For attachment, an adhesive or a known conventional method for fixing the device to the rubber composite can be used.

  Referring to FIGS. 2 and 3, the annular storage tube 36 of the present invention houses the antenna 32 therein, preferably but not in a relaxed state. The tube 36 is preferably made of an elastic fiber such as spandex, rubber, or vinyl, and may be formed of other synthetic materials having sufficient flexibility. The antenna cable 32 may be either a single wire or a stranded wire of a plurality of wires.

  When the tube 36 configured in this manner is installed in a tire and receives a stress existing in the tire, the tube 36 is bent or stretched, and shifts from an initial loose state to a stretched state. Since the antenna 32 has a wave shape, a sinusoidal shape, or a zigzag shape, the antenna 32 is straightened or bent in the tube to absorb the extension of the tube 36. When released from the effects of tire stress, the tube recovers and attempts to shrink to the initial, optimal tube shape. The outer wall of the tube 36 may be straight or corrugated to provide more flexibility (not shown).

  As is apparent from FIGS. 2 and 3, the electronic component package 34 stores electronic components of a type that is commercially available and generally used. The electronic component may include one or two or more sensors that monitor the internal state of the tire and connection means for connection to the antenna 32. Both ends of the antenna 32 may be soldered to terminals inside the package 34 to provide a means for transmitting input / output signals between the sensor package and an external reader (not shown), for example. Good. Package 34 includes a base housing 38 that is not required but is generally cylindrical in shape and through which access axial bore 40 passes. The hole 40 extends between opposite end portions 42 and 44 of the housing 38 and serves as a connection means with internal electronic components housed in the housing 34.

  The housing ends 42, 44 may be protrusions or nipples extending from the housing 38 in one embodiment of the invention. Also, the ends 42, 44 may be flush with the side of the housing 34 if desired. Ends 42 and 44 refer to sockets having a shape and an inner diameter that can receive both ends of tube 36 entering therein. The ends 42, 44 and the tube 36 may also be shaped such that the ends 42, 44 are within the ends of the tube 36. In the illustrated embodiment, the end of the tube 36 is press fit into the ends 42, 44 of the housing 38. In order to maintain the fitting state between the tube and the housing, an adhesive may be applied to the outer surfaces of both ends of the tube. If desired, an annular recess 46 is formed in each housing end 42, 44, and the recess 46 has a complementary shaped annular shoulder 48 formed to protrude from each end of the tube 36. You may make it accept. When the shoulder 48 engages the recess 46, the tube is mechanically coupled to the housing.

  The method of assembling the tube 36 with the housing 38 and electrically connecting the antenna 32 to the electronic components within the housing 34 is thus direct and efficient. The assembling method includes a step of accommodating the extendable antenna cable 32 in a tube 36 having a hole extending in the axial direction in the central portion and having both ends of the hole open, preferably relaxed, and each end of the tube. A step of storing an electronic component in a package 34 having end portions 42 and 44 formed in a shape and size that can be fitted to the portion, and connecting both ends of the antenna cable 32 to the electronic component stored in the package And attaching both ends of the package to both ends of the antenna tube for attaching the antenna housing to the electronic component package.

  From the foregoing, it will be appreciated that the present invention satisfies the need in the art for a convenient and reliable mounting method for mounting an annular antenna inside a tire. By making the tube 36 of resilient fiber material, rubber, vinyl, or similar materials, a containment is formed that protects and maintains the antenna contained therein in an optimal shape. The tube 36 can be manufactured economically and is effective. The tube extends from its initial relaxed state when stress is applied in the tire. Such elongation is absorbed by the tube material and the curved shape of the antenna. The recovery characteristics of the tube to its original shape provide sufficient predictability and durability to withstand the number of stretch / recovery cycles required for typical tires used in the intended manner. Have. Lycra Spandex (registered trademark of E.I. DuPont de Nemours & Company) is an example of a material that can be used. Other commercially available stretchable fabrics can be used as well. Textiles having selected elongation resistance, residual stress, hysteresis, residual elongation, and recovery properties can be used. The material generally has a cycle limit that represents the maximum amount of elongation that the material can withstand without permanent deformation. Further, the holding force and elongation resistance may be selected so that the elastic properties of the tube 36 and the amount of elongation resulting from stress in the tire environment are optimally balanced.

  The advantages of the present invention over an antenna device comprising a rubber support strip are significant. A structure consisting of spandex fiber, rubber, vinyl tube can be repeatedly pulled and can recover to very close to its initial length and strength. The material can be pulled over multiple cycles without breaking. The material is stronger, more durable and provides greater resilience.

FIG. 3 is a perspective view of the tire and the annular device of the present invention, with a portion of the tire cut off for illustration purposes. FIG. 3 is an enlarged perspective view, partially disassembled, of an antenna tube assembly and an electronic component package. FIG. 3 is a side view of the antenna tube assembly and electronic component package, partly shown in cross-section for illustration.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Apparatus 12 Tire 22 Inner liner 24 Tire space 32 Antenna 34 Transponder module 36 Storage tube 38 Base housing 40 Axial hole 42,44 End 46 Recess 48 Shoulder

Claims (3)

In tire equipment,
An extendable antenna;
An elongate, tubular antenna housing made of a material with suitable flexibility, comprising an axial hole for receiving the elongate antenna and extending between opposite ends of the antenna housing An antenna housing provided; and
An electronic component package having an outer end, the outer end having a size and a shape that respectively fit with the opposite ends of the antenna housing, whereby the antenna housing is in the electronic component package And an electronic component package attached to the tire.   The tire device according to claim 1, wherein the antenna is housed in a relaxed state in the axial hole of the antenna housing. In the tire with the antenna assembly built in,
A tire body having a wall facing inward;
An extendable antenna;
An expandable, tubular antenna housing, attached to the inwardly facing wall of the tire body, made of a suitable flexible material, receiving the extendable antenna, and the antenna housing An antenna housing having an axial hole extending between the openings at the ends on both sides thereof;
An electronic component package having an outer end, wherein the outer end is provided on an opposite surface of the antenna housing, and engages with the opposite end of the antenna housing, whereby the antenna housing is An electronic component package attached to the electronic component package.

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